It is no mystery why the National Football League's (NFL) Ravens have been embraced by the city of Baltimore after being imported from Cleveland 17 years ago.

A Super Bowl triumph in 2001, nine playoff berths and a shot at hoisting the championship Lombardi Trophy for a second time on February 3 when they face the San Francisco 49ers in New Orleans has helped the Purple-and-Black win hearts in the Charm City.

Jilted by their long-beloved Colts, three-time champions of the old NFL and winners of the 1971 Super Bowl who relocated to Indianapolis overnight in moving vans, Baltimore took a while to warm to their new team.

Baltimore, home of the Colts for 30 years, waited 13 years for the NFL's return, provided when the late Cleveland Browns owner Art Modell moved his team to Maryland.

It was renamed the Ravens after a telephone poll chose the moniker, alluding to the famous poem "The Raven" by mystery and horror tale author Edgar Allan Poe, who spent the early part of his career in Baltimore.

It would be a fresh start for the team, who took University of Miami linebacker Ray Lewis with the 26th pick in the first round of the 1996 NFL Draft.

It was all so new then, of course, for both Lewis and the Ravens.

"In 1996 when they drafted me, the first thing I asked was, 'Do we have a team name? What are our jersey colors going to be and all that?"' Lewis recalled asking Ravens general manager Ozzie Newsome over the telephone.

Lewis, the Ravens' senior citizen in NFL years, will crown 17 seasons in Baltimore with a retirement party after playing the Super Bowl.

While the Baltimore Colts became famous on the golden arm of quarterback Johnny Unitas, the sure hands of Raymond Berry and the fluid running of Lenny Moore - all three members of the Pro Football Hall of Fame - the Ravens were built on defence.

They went 4-12 in their debut season under coach Ted Marchibroda, a former Colts head coach, and in their fourth season, the Ravens replaced him with Brian Billick, who had been offensive coordinator for the high-scoring Minnesota Vikings.

STAUNCH DEFENcE

Billick improved the Ravens from 6-10 to 8-8 but in the next season the defence blossomed into a terrorizing force under defensive coordinator Marvin Lewis while number one draft pick Jamal Lewis from Tennessee emerged as an elite running back.

After a 5-4 start to the 2000 season, Billick switched quarterbacks from Tony Banks to Trent Dilfer, and a conservative offence paired with the ferocious defense to dominate the NFL.

They won 11 straight games from that point, culminating in a 34-7 thrashing of an intimidated New York Giants team in the Super Bowl played in early 2001.

Baltimore's defence set an NFL record for fewest points allowed in a 16-game season (165), Lewis was named Defensive Player of the Year and made the Pro Bowl along with defensive team mates Sam Adams and Rod Woodson.

Billick remained in charge for seven more seasons that included three more trips to the postseason, but was replaced after a 5-11 season in 2007 by John Harbaugh, getting his first head coaching job after years as a special teams coordinator for the Philadelphia Eagles.

The Ravens had relied on their staunch defence, fueled by the likes of Lewis, Terrell Suggs, Ed Reed and Haloti Ngata, and their list of defensive coordinators has included Marvin Lewis, Mike Nolan, Rex Ryan and Chuck Pagano - all of whom graduated to head coaching jobs.

By contrast, their list of quarterbacks was much less impressive, numbering Banks, Dilfer, Elvis Grbac, Jeff Blake, Kyle Boller and a fading Steve McNair.

The revolving door at quarterback changed with the drafting of Joe Flacco from the University of Delaware, who arrived the same year as Harbaugh.

Since they hit the scene together in 2008, the Ravens have reached the playoffs five seasons in a row, the only NFL coach and quarterback ever to have achieved that feat.

Their 62 wins over the last five years, including playoffs, is second only in the NFL to the 63 games won by New England, who the Ravens beat 28-13 in the AFC title game on Jan. 20.

Baltimore, whose offence featuring versatile running back Ray Rice and a crew of dangerous receivers including Torrey Smith, Anquan Boldin and tight end Dennis Pitta, has become more balanced and a full partner with the defence in the team's pursuit of a second Super Bowl crown.